/Engine/Plugins/Runtime/AR/AppleAR/AppleARKitFaceSupport/Source/AppleARKitFaceSupport/Private/AppleARKitLiveLinkSource.h
Adds a substring to the buffer
[FNboSerializeToBuffer](API\Plugins\OnlineBase\Online\FNboSerializeToBuffer) & AddString ( const ANSICHAR * String, const int32 Length )